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H. M. PFISTER.

RELEASING WRENCH FOR COAL CARS. APPLICATION men OCT- 23. m4.

1,304,090. Patented May 20,1919.

WI2NE88E8 INVENTOR 4 2g; 6. /V. M 0 a A TTQRNEY HARRY M. PFISTER, or srivenan'roiv, NEW YORK.

RELEASING-WRENCH FOR COAL-CARS.

Specification of Letters Patent.

Patented May 20, 1919.

Application filed October 23, 1914. Serial No. 868,244.

To all whom it may concern:

Be it known that I, HARRY M. PrIs'rER, a citizen of the United States, residing at Binghamton, in the county of Broome and State of New York, have invented certain new and useful Improvements in Releasing- WVrenches for Coal-Cars, of which the following is a specification.

My invention relates to an improvement in car wrenches for releasing a chain shaft of trap doors in coal cars, wherein I have mounted within a handle a casing and revolving socket capable of being placed over the chain shaft of the car doors as before stated, having within it means for automatically releasing the revolving shaft so that the shaft will revolve after the leverage applied through the handle has ceased and the shaft gear released without turning the handle of the wrench.

With these objects in view, my invention consists. of certain novel features of construction and arrangement of parts as will be hereinafter more particularly pointed out in the claims, reference being had to the accompanying drawings in wh1ch:-

Figure 1 is a perspective view of my device applied to or mounted on the chain shaft of the doors of a coal car.

Fig. 2 is a side elevation of my device with a portion of the casing removed and the handle shown broken away.

Fig. 3 is an end elevation of my device with the casing broken away.

Fig. 4: is a similar view of a modified form.

The same reference characters denote like parts in each of the several figures of the drawings.

In carrying out my invention, I provide a circular casing A having a handle projection B. Within the casing A I have the disk G having in the center of its outer edge surface a line of teeth 2, 2, 2, &c., and through the body portion of the disk a rectangular opening D. Pivotally mounted on the inner surface of casing A, I have the pivoted dogs 3. 3. 3, &c., pivotally mounted on ears 4. 4 as clearly shown in the drawings. On the inner edge surface also of A, I have mounted the springs5. 5. 5, &c, having contact with and exerting yielding pressure upon said dogs 3 causing the dogs to be held in contact with the teeth 2. 2.

In a preferred form of my device as shown in Fig. 3, on either side of the teeth line 2. 2. 2, I have the rollers 6. 6 mounted on pivots passing between the sides of the casing A. The disk C in its turning rests upon and has contact on its edge surface with said rollers 6. 6. 6, &c.

In a modified form of my device I have the casing A and mounted within it the revolving disk C having on the one-half of the edge surface of said disk the line of teeth 2. 2. 2 projecting therefrom and hav ing also mounted within it the dogs 3. 3. 3 which have contact with said teeth 2. 2. &c.,

and mounted between said line of teeth and the inner surface of the side of casingA I have said rollers 6. 6 operated in a similar manner as in the preferred form of my device.

In the operation of my device I place the opening D over the projecting end of the chain shaft of the trap doors of a coal car and having in any convenient manner first released the dog 7'. If the doors of said cars do not open bythe unwinding of the chain, I bear down upon the handle B of the wrench, the leverage movement or pressure on the shaft E will have a tendency to loosen shaft E and it will revolve, turning to the left as seen in Fig. 1 and moving with 1 it as-it turns the disk C within the casing A, thus allowed to move freely within the casing while the handle B of the casing A is not turned. So the rapidly moving shaft E can be started in its movement by prying upon the handle B of the wrench when applied to shaft E and shaft E started in its revolving movement and the handle held until it has completed its revolutions by the unwinding of the chain caused by the drop ping of the doors 8. 8 in car F. The shaft E being unwound the wrench is then removed from the shaft.

Having thus described my invention, what I claim as new and for which I desire Letters Patent is as follows:

1. A device of the class described comprising a hollow cylindrical casing having a central opening therethrough, a handle projecting from said casing, a disk mounted within the casing and provided with a squared central opening, a row of ratchet teeth on the periphery of the disk, a roller bearing track way also on the periphery of the disk at one side of the row of ratchet teeth, spring pressed dogs pivotally secured to the casing and engaging the ratchet teeth and roller bearing elements interposed between the casing and the track way on the disk and positioned between the dogs.

2. A device of the class described comprising a cylindrical hollow casing having a central opening therethrough, a handle projecting from said casing, a disk within the casing and provided with a squared central opening, a row of ratchet teeth on the periphery of the disk, roller bearing track ways on the periphery of the disk at each side of the row of ratchet teeth, a series of spring pressed dogs pivotally mounted within the casing and engaging the row of ratchet teeth, and roller bearing elements interposed between the disk and the casing and operating on the track ways at each side of the row of ratchet teeth, said roller bearing elements being positioned between the spring pressed dogs.

3. A device of the class described, comprising a cylindrical hollow casing having a central opening therethrough, a handle projecting from said casing, a disk within the casing and provided with a squared central opening, a row of ratchet teeth on the periphery of the disk, a roller bearing track way also on the periphery of the disk at one side of the row of ratchet teeth, spaced ears projecting radially inwardly from the interior periphery of the casing and disposed out of alinement with the row of ratchet teeth, spring pressed dogs pivotally mounted in the ears at one side thereof and in alinement with the ratchet teeth to engage the same and roller bearing elements interposed betlvzveen the casing and the track-way of the dis 4:. A device of the class described comprising a cylindrical hollow casing having a central opening therethrough, a handle projecting from said casing, a disk within the casing and provided with a squared central opening, a row of ratchet teeth on the periphery of the disk, roller bearing track- Wayson the periphery of the disk at each side of the row of ratchet teeth, a series of spaced ears projecting radially inwardly from the interior surface of the casing and.

disposed to one side of the row of ratchet teeth of the disk, a second series of spaced ears projecting radially inwardly from the interior surface of the casing and disposed at the other side of the row of ratchet teeth on the disk, corresponding .ears of each series being disposed in alineinent transversely of the casing, spring pressed dogs pivotally mounted between corresponding ears of the two series of inwardly projecting ears and having engagement with the row of ratchet teeth, and roller bearing elements interposed between the disk and the casing and operating on the trackways at each side of the row of ratchet teeth.

In testimony whereof I have affixed my signature in presence of two witnesses.

HARRY M. PFISTER.

Vitnesses:

E. A. J OYNER, WALTER CHARLES.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patent: Washington, D. G. 

